Answer:
Step-by-step explanation:
When completing the square, an expression like,
ax2 + bx + c is written in the form (Ax + B)2 + C.
We will begin with the simple example where a = 1. In this case we will write expressions in the form
x2 + bx + c as (x + B)2 + C
If we expand (x + B)2 + C we get x2 + 2Bx + B2 + C.
Comparing this with x2 + bx + c shows that
b = 2B and c = B2 + C
which gives B =
b
2
and C = c – B2
